Grinding machine



Nov. 27, 1934. v F AAS 1,9 2,297

Q GRINDING NAcHINE I Filed April 4, 1952 5 Sheets-Sheet 2 NQV. 27 1934. s HAAS 1,98Z,g7'

GRINDING MACHINE Filed April 4, 1952 3 Sheets-Sheet 5 Patented Nov; 27, 1934 UNITED STATES 1,982,297 GRINDING moms Frederick s. Haas, Cincinnati, Ohio. assignor to Cincinnati Grinders Incorporated, Cincinnati,

Ohio, a corporation of Ohio Application April 4, 1932, Serial No. 603,048

3 Claims.

This invention relates to improvements in machine tools and particularly toimprovements in grinding machines. v

An object of the invention is the provision of,a machine for grinding surfaces of revolution such as a centerless grinder, whichincludes a grinding wheel and regulating wheel, together with improved means for truing the active faces of said wheels.

Another object of thednvention is the provision of improved means for truing the active face of the regulating wheel of a centerless grinder.

A further object of the invention is the provision ofimproved control means for effecting and controlling the operation of a truing mechanism associated with a machine tool organization for truing or trimming the active face of a tool or grinding wheel.

A still further object of the invention is the provision of improved hydraulic means for actuating and controlling an abrasive wheel truing device.

Other objects and advantages of the present invention should be readily apparent by reference to the following specification considered in conjunction with the accompanying drawings, forming apart thereof, and it is to be understood that any modifications may be made in the exact structural details there shown and described within the scope of the appended claims without departing from or exceeding the spirit of the invention.

In the drawings:

Figure 1 is an elevational view of a grinding machine embodying the improvements of this invention.

Figure 2 is'a fragmentary plan view of a portion of the machine shown in Figure 1.

Figure 3 is a sectional view as seen substantially from line 3-3 on Figure 2. Figure 4 is a' sectional view taken on,line 4-4 of Figure 2.

Figure 5 is a view partly in section and partly in elevation as seen from line 5-5 ,on Figure 3.

Figure 6 is a sectional view taken on line 6-6 .of Figure 4.

Figure 7 is a sectional view taken on line 7-7 of Figure 2.

Figure 8 is a sectional view taken on line 8- -8 of Figure 5. 1

Figure 9 is a fragmentary sectional view taken on line 9-9 of Figure 3.

Figure 10 is a sectional view taken on line 10--10 of Figure 5.

Figure 11 is a diagrammatic 'view ofthe hy- -of the grinding wheel and regulating wheel or draulic circuit involved in the control and operation of the invention.

Throughout the several views of the drawings similar reference characters are employed to de note the same or similar parts.

In centerless grinders as commercially used today the regulating or control wheel is made of suitable abrasive material and bears a definite relation to the opposedgrinding wheel and the work rest blade and is adapted to contact with the work on a line parallel with the axis of the work and grinding wheel for effecting the proper .control of the work. This condition exists even though the axis of the regulating wheel is disposed at a slight angle to the axis of the work and grinding wheel for effecting a feed component on or axial travel of the work. The work is further adapted to be ground with its axis or center either aligned with the axes or centers with the said work axis either above or below the line joining the centers of said wheels and the active face of the regulating wheel must be trued in accordance with these several variable factors for establishing and maintaining a line contact between the said wheel and. the work. The mechanism for accomplishing these several conditions will be amply described in detail below.

As shown in the drawings, the machine embodies a bed 10 disposed substantially vertically with the operative or supporting surface disposed at an oblique angle to the vertical and having formed thereon a guideway 11 for guiding a grinding wheel carriage 1-2 in its movement relative to the bed. The grinding wheel carriage has journaled therein a spindle 13 to which is secured a grinding wheel 14 for rotation therewith. The spindle 13 haasecured to it a pulley 15 about which is trained a flexible or belt transmission 16 which is in turn disposed about a pulley on the belt tightener shaft 17. The belt tightener shaft 17 is carried by an arm 18 in turn pivotedto a supporting shaft or pivot 19 carried by the bed 10. The shaft 17 is further provided with a second pulley about which the flexible transmission or belt 20 passes, being in turn trained about a pulley or sheave 21' carried by the motor shaft 22. The motor shaft 22 is associated with a prime mover, here shown as an electric motor 23 disposed on a bracket 24 interiorly of the bed 10.

The motor 23 is adapted to be rotated at a suitable speed for rotating the grinding wheel 14 8. high grinding rate of speed through the 110 transmission or belts 20 and 161 for thereby effecting stock removal from the work.

The grinding wheel carriage 12 has depending from it interiorly of the bed 10 a lug or arm in which is journaled a nut 26 adapted to be rotated relative to the arm or lug 25. The nut 26 is in threaded engagement with an adjusting screw 27 carried by the bed at 28 and 29 interiorly thereof and thereby held against rotative movement. In order to rotate the nut 26 it has formed integral therewith or secured thereto a worm wheel 30 which has meshing therewith the worm 31 formed on one end of a shaft 32. The shaft 32 passes through suitable bearings formed integral with or secured to the carriage 12 and is provided on its outer end with a hand wheel or the like 33 whereby it may be actuated. From the foregoing it will be seen that rotation of the hand wheel 33 and worm 31 effects the rotation of the worm wheel 30 and nut 26 thereby causing said nut to be adjusted axially to the screw 2'7 carrying with it the grinding wheel carriage 12.

Secured to the bed 10 along the oblique supporting surface thereof is a bracket 34 having secured to it for adjustment about the axis of pivot stud 35 a wheel head 36 in which is journaled the regulating wheel spindle 37 having secured to it the regulating wheel 38. The head 36 is adapted to be secured in its adjusted positions by means of clamp bolts 39 passing through elongated perforations formed in the bracket 34.

The opposed peripheries of the grinding wheel 14 and regulating wheel 38 are adapted to be disposed from one another a distance equal to the final size of the work piece 46 being operated upon and thereby forming a grinding throat. The work 40 is supported by a work rest blade 41 having an operative surface 42 disposed. beneath the grinding throat. The operative surface. 42 of the blade 41 inclines in the direction of the regulating wheel and forms with said operative surface a work receiving trough. The blade 41 is secured to a work rest block 43 secured to the bed at a point below the grinding throat.

The regulating wheel and its spindle are adapted to be rotated by any suitable or desirable means at a comparatively slow work controlling rate of speed in a clockwise direction for causing the operative face of the wheel to travel upwardly as respects the blade and the work supported thereby. As was noted above, the grind ing wheel 14 is adapted to be rotated ata high grinding rate of speed and in a clockwise direction whereby its operative face travels downwardly as respects said blade for causing the same to take the grinding thrust on the work.

From this it will be seen that the work is in simultaneous contact with the grinding and regulating wheels for stock removal therefrom and for controlling its rotation during said stock removal.

In order to true the active face of the regulating wheel 38 its head 36 has secured to it a housing or bracket 44 semi-circular in cross section as seen in Figures 3 and 8, being formed on one side with a dove-tailed guideway 45 receiving a correspondingly formed guide tongue 46 formed on the adjacent surface-of a slide 47. The slide 4'7 is formed with a transverse dove-tailed guideway 48, see Figure 5, receiving a similarly shaped tongue 49 formed on the transverse slide 50. All unnecessary play between the guideway 48 and tongue 49 being taken up by means of a gib 51, while the unnecessary play between the guideway 45 and tongue 46 is likewise eliminated by the gib 52. The transverse slide 50 is formed with a substantial barrel guide or sleeve 53 in which is disposed the axially movable post or bar 54 having secured therein a nut 55 which is held against both axial and rotative movement. Threaded into the nut 55 is an adjusting screw 56 having a collar 5'7 near one end and a reduced portion 58 journaled in a pilot guide 59 fastened in the upper end of the barrel guide or sleeve 53. Beyond the pilot 59 the reduced portion 58 has secured thereto an operating knob 60 whereby the screw is rotated for axially adjusting the bar 54. The bar 54 is restrained against rotative movement by a keyway or groove 61 formed longitudinally thereof and receiving a suitable key or boss 62 projecting inwardly from the barrel guide or sleeve 53.

The barrel guide or sleeve 53 has projectingfrom its lower end a boss or lug 63 through which slidably passes a pin 64 which is carried by a boss or lug 65 projecting from the longitudinal slide 47. Surrounding the guide pin 64 is a'spring 66 abutting on one end with the lug 63 and on the other end with the lug 65 and axially urging the transverse slide 50 in one direction or toward the regulating wheel, as seen in Figure 8. This transverse shifting of the slide is limited by means of a pin or the like 6'7 projecting from the slide 50 through a suitable aperture 68 formed in the longitudinal slide 4'7. The pin 67 abuts the upper or cam surface 69 of a cam bar '70 adjustably secured to lugs '71 extending upwardly from the housing 44.

,The lower end of the bar 54 has a transverse opening '72 receiving therein a split block 73. The block '73 is provided at its lower end with a dovetailed guideway or groove '74 receiving'a correspondingly shaped tongue '75 projecting from the truing .tool or diamond carrier 76. The carrier '76 has fastened in it as by means of a clamp screw or the like '77, the diamond holder '78 in which is secured the diamond or other truing tool '79. One side of the carrier '76 is provided with suitable graduation marks and indicia co-operating with a zero mark or pointer 81 for adjustably determining the position of the diamond relative to the bar and whether the work is being ground above or below the line joining the axes or centers of the grinding and regulating wheels.

From the foregoing it will be noted that there has been provided a truing tool or diamond support that may be adjusted toward and from the operative face of the regulating wheel and which may further be adjusted relative to the operative face for truing said face for proper line contact with the work regardless of the position of the work with respect to the axes of the wheels.

In order to further true the active face of the regulating wheel to obtain line contact between it and the work, especially when the regulating wheel is adjusted about the axis of the trunnion 35, the housing 44 is adapted to beadjusted in a plane horizontal to the plane of the axis of the work and relative to the axis of the regulating wheel and its spindle for which purpose there is provided a pivot pin 82, see Figure 3, carried by the head 36 and received in a pocket or the like 83 formed in the housing 44. To clamp the housing in its several positions it is provided with a pair of arcuate slots or perforations 84 and 85, each having at one end thereof an enlarged opening 86 through which the head of the clamp bolt 87 passes. The housing 44 is further provided with an undercut or slot 88 into which the head 89 of the bolt v87 is positioned. The bolt 87 is slidably mounted in an aperture 90' formed in the head 36 and has formed intermediate its ends a cam slot to provide a cam face 91 co-operating with the cam shaped nose 92 of a sliding clamp pin 93. The said pin is received in a socket formed in a, clamp bolt 94 carried by the head 36 in alignment with the clamp bolt 87.

The operation of these parts is as follows. The clamp bolts94 are backed away to relieve the clamping pressure between the cams 92 and cam faces 91 whereupon the housing 44 may be oscillated about the axis of the pivot 82. After the housing is adjusted to the desired position, the clamp bolts 94 are then fastened or screwed home for pulling down on the clamp bolts 87 through the interengagement of the cams 92 and cam faces 91.

In order to traverse the slide 47 and parts carried thereby across the .face of the regulating wheel in whatever position of adjustment the housing 44 may be disposed, the slide 47 has secured to it by cap screws 95, see Figure 5, a cylinder head 96. This head 96 is provided with an external screw on which is fastened one end of a 3 cylinder 97 having the other end closed in any suitable or desirable manner,as by the head 98,

- see Figure 2. Interiorly of the cylinder 97 is disposed a piston 99 fixed against axial movement as bymeans of a piston rod 100. In order to prevent ieakage through the head 96, it carries suitable packing and packing gland 101 surrounding the piston rod where it passes through the said head. v

The piston rod 100 is in the nature of a tube or pipe having on one end the nut 102 for securing the piston between itself and a shoulder formed on the piston rod or tube. The other end being in communication with the end 102a of the piston rod 100, while the latter is in communication with a hollow tube or pipe 107 of a diameter less than the diameter of the bore through the piston rod 100 and extending entirely therethrough, terminating within the cylinder 97. The

piston rod 100 is provided adjacent the piston with a port 108 communicating with the cylinder 97 between the head 96 and adjacent face of the piston 99.

' The valve casing 104 has oscillatably mounted therein a two way valve plug 109 having formed intermediate its ends flats 110 and 111, which are diametrically opposite one another. The chamber communicates with the valve flat by means of a port or duct 112, while the chamber 106 of said boss 103 connects through the port ofduct 113 and port or duct 114 with the valve flat 111. The valve fiat 110 is also in communication through a port or duct 115 with a pressure conduit or line 116 while the valve flat 111 communicates through a port or duct 117 with a, passage 118 extending centrally through the valve plug 109 terminating in a transverse port or duct 119 formed in the valve plug 109. The valve plug 109 is formed with a circumferential groove 120 around the transverse duct 119 and is in communication with a port 121 formed in the valve casing 104 which empties into a second port 122 controlled-by a needle or choke valve 123. The port 122 after passing the needle or choke valve 123 communicates with a pipe or conduit 124.

As shown in Figure 11, the pipe or conduit 116 is connected with the discharge side of a pressure pump 125 which has its intake side connected by a pipe or conduit 126 with a supply tank or sump 127 containing an hydraulic medium, preferably oil, adapted to be circulated through the system for actuating the piston and cylinder relative to. one another. The pipe 124 terminates in the tank or sump for returning the spent or used medium to the tank. 7.

The valve plug 109 is provided at its forward end with a reduced stem portion 128 which passes out through a packing gland or the like 129 and carries a lever or handle 130 whereby the plug is oscillated ior connecting the pressure and the exhaust pipes 116 and 125 alternately with the piston rod tube 100 and tube or pipe 107. To

I maintain the plug valve in itsdesired position the casing is closed on the end opposite to the handle 130 with a cap 131 in which is formed a socket 132 receiving a compression spring 133 abutting the face ofthe socket and the adjacent end of the plug 109 and yieldingly urging the plug to the left, as seen in Figure4.

In order to limit the oscillation of .the plug valve in oppositedirections, it is formed intermediate its ends with a notch 134 into which the tip of a stop screw 135 projects being adapted to engage the ends of the notch or fiat 134 and thereby limit the oscillatory movement of the plug in each direction.

The operation of the hydraulic mechanism is as follows. With the plug valve 109 in the position shown in Figures 4, 6'and 7, the pressure from the pipe or conduit 116 is directed by the fiat 110 to the port 112 and chamber 105 causing the medium to pass through the piston tube 100. The hydraulic pressure then enters the cylinder 97 through the port 108 between the piston 99 and adjacent surface of the piston head 96. The pressure reacts on the adjacent surfaces ofthe piston 99 and head 96 causing the cylinder 97 to travel to the left, as seen in Figure 5. The movement of the cylinder in this direction carries with it the slide 47 and the parts carried thereby.

actuate the transverse slide 50 relative to the guide-way 48 toward the grinding wheel, while if the said bar is provided with an inclined sin'face inclining in an upward direction it will through the pin 67 lift the slide away from the operative surface of the regulating wheel against the yielding resistance of the said spring 66.

During the movement of the cylinder as above described, the hydraulic medium contained therein between the face of the piston and the fixed head 98 of the cylinder, will be forced outward through the tube 107 lying within the bore in the piston tube 100. This medium will be discharged through the tube 107 to the ports 113 and 114 to the fiat 111 where it will be directed through'the ports 117 and 118 to the transverse port 119 to the main return or exhaust conduit 124. The said exhaust medium will pass into the conduit 124 only at the rate that the needle or choke'valve 133 permits such escape, which cylinder 97 relative to the piston 99 and thereby 7 head 36.

the rate of travel of the tool across the grinding wheel.

The head 36 is provided with an opening 136 through which the truing tool bar 54 passes into contact with the wheel. It will be noted that this opening is of a seemingly unnecessary width, whichis desirable in order to take care of the adjustment of the bracket 4.4 in a horizontal plane. In order to prevent the coolant spray from escaping from the head either during truing or during the normal operation of the machine, this opening is closed by a pair of guard plates 137 and 138 superimposed on one another and overlapping for a certain portion of their length. 'As shown in Figure 5, the upper plate 138 has merely a circular aperture through which the bar 54 passes, while the lower guard plate 137 is provided with an elongated aperture 139. Between the traverse slide barrel or guide sleeve 53 and the upper guard plate 138 there is disposed a coiled spring 1&0 contacting on one end with the lower end of the barrel or guide sleeve and on the other end with the top surface of the top guard plate 138.

The spring 140 maintains proper engagement between the contacting surfaces of the plates 136 and 137 and the contacting surfaces of the lower plate 137 and upper surface of the head 36 so thatthe said plates do not become disengaged or misaligned through gravity or other causes. During operation the movement of the slide 47 carrying with it the parts supported thereby moves the tool bar 54 and the upper guard plate 138, moving same relative to the lower guard plate 137. This relative movement continues until the end of the lower guard plate aperture 139 is reached whereupon the bar picks up the said lower plate moving the two plates as a unit relative to the head 36. It should be noted that the size of these plates is sufficient at all times to keep the aperture 136 covered and thereby prevent escape of the coolant spray from within the From the foregoing it will be noted that there has been provided an improved truing mechanism for truing the operative surface of the regulating wheel under all conditions of operation together with an improved hydraulic control mechanism for effecting and controlling the operation of the truing device.

What is claimed is:

1. An apparatus for truing the peripheral face of the regulating wheel of a centerless grinder to have line contact with a work piece when the axis of the regulating wheel is angularly disposed to the axis of the grinding wheel and work piece, the combination of a housing for the regulating wheel, a bracket on said housing and disposed to one side of the axis of the wheel and said bracket having a face normal to the housing, means pivotally connecting the bracket to the housing with the axis of said pivot means laterally offset with respect to the axis of'the wheeland disposed at a point substantially midway of the length of the wheel face, said normal face of the bracket having formed therein a dovetailed guideway, a slide mounted in said dovetailed guideway for movement relative thereto across the face of the regulating wheel, a truing tool mounted on said slide for movement therewith, means forsecuring the bracket in angular position relative to the housing, the housing having an aperture therein through which the truing tool passes to engage the wheel face and said aperture being of such dimensions as to permit free movementof the tool regardless of the angular adjustment of the bracket relative to the housing, and hydraulically actuable means for effecting the movement of the slide and truing tool relative 'to the bracket. 2. An apparatus for truing the peripheral face ofthe regulating wheel of a centerless grinder to have line contact with a work piece when the axis of the regulating wheel is angularly disposed to the axis of the grinding wheel and work piece, the combination of a housing for the regulating wheel, a bracket on said housing and disposed to one side of the axis of the wheel and said bracket having a face normal to the housing, means pivotally connecting the bracket to the housing with the axis of said pivot means laterally offset with respect to the axis of the wheel and disposed at a point substantially midway of the length of the wheel face, said normal face of the bracket having formed therein a dovetailed guideway, a slide mounted in said dovetailed guideway for movement relative thereto across the face of the regulating wheel, a truing tool mounted on said slide for movement therewith, means for securing the bracket in angular position relative to the housing, the housing having an aperture therein through which the truing tool passes to engage the wheel face and said aperture being of such dimensions as to permit free movement of the tool regardless of the angular adjustment of the bracket relative to the housing, and hydraulically actuable means for effectingthe movement of the slide and truing tool relative to the bracket, comprising a cylinder secured to the slide, a piston within the cylinder, a hollow piston rod having one end secured to the piston and the other 110 to the bracket for'maintaining the piston in a definite position, the piston rod communicating with the cylinder on one side of the piston, a pipe extending through the interior of the piston rod and communicating with the cylinder on the 1 5 other side of the piston, and valve means for alternately connecting a fluid under pressure to the piston rod and pipe and therefore the opposite sides of the piston to actuate the cylinder and slide relative to the piston.

3. An apparatus for truing the peripheral face of the regulating wheel of a centerless grinder to have line contact with a work piece when the axis of the regulating wheel is angularly disposed to the axis of the grinding wheel and work piece, 1 5 the combination of a housing for the regulating wheel, a bracket on said housing and disposed to one side of the axis of the wheel and said bracket having a face normal to the housing, means pivotally connecting the bracket to the housing with the axis of said pivot means laterally offset with respect to the axis of the'wheel and disposed at a point substantially midway of the length of the wheel face, said normal face of the bracket having formed therein a dovetailed guideway, a slide mounted in said dovetailed guideway for movement relative thereto across the face of the regulating wheel, a truing tool mounted on said slide for movement therewith, means for securing the bracket in angular position relative to the housing, thehousing having an aperture therein through which the truing tool passes to engage the wheel face and said aperture being of such dimensions as to permit free movement of the tool regardless of the angular adjustment of the bracket relative to the housing, and hydraulically actuable means for effecting-the movement of the slide and truing tool relative to the bracket, comprising a cylinder secured to the slide, a piston within the Cylinder, 150

a hollow piston rod having one end secured to the piston and the other to the bracket for maintaining the piston in a. definite position, the piston rod communicating with the cylinder on one side of the other end of the piston is connected'while the other has connected therewith the other end of the pipe, and a valve member in said casing for alternately connecting a hydraulic medium under pressure with said chambers and therefore the piston rod and pipe for eflecting the movement of the cylinder and slide relative to the bracket. I FREDERICK B. HAAS. 

